slender filaments, and cylindrical articulations sufficiently distin- 
guish it. It agrees better in these respects with the rare 
G. barbata, but differs in its mflorescence, if 1 may venture to 
use that term to express the disposition of fruit. 
The genus Griffithsia, proposed by Agardh, in 1824, has been 
universally adopted by botanists, and now includes nearly thirty 
species, scattered through the seas of all temperate climates, and 
reaching even to the troubled ocean of Cape Horn. One species 
is tropical; several of great beauty are found in the Mediterra- 
nean ; and the shores of Australia, the Cape of Good Hope, and 
Western South America contribute others. All the species possess 
a common property, that of beimg exceedingly impatient of the 
contact of fresh water. To secure well-preserved specimens they 
should be brought home in salt water, and kept in it till they can 
be laid on paper. A short exposure to air is sufficient to decom- 
pose them, and fresh water causes the membrane of the cells to 
burst, and the colourmg matter to be discharged with violence, 
as well described by Dr. Drummond in Loudon’s Magazine of 
Natural History. 
The genus is nearly allied to Callithamnion, and still more 
nearly to Wrangelia, from which latter it is chiefly distmguished 
by having the tetraspores imvolucrated. 
Fig. 1. Grrrrirus1a Drvonrensis :—uatural size. 2. Upper portion of a 
filament. 3. Involucre. 4. Ramulus of ditto, shewing the position of 
the tetraspores. 5. A tetraspore. 6. Apex of a filament, to show the 
form of the articulations :—all more or less magnified. 
